Fighting Against Our Nature
by Colonel Sugar
Summary: Izuku Midoriya is a young Omega that hasn't gone into his first Heat yet. That all changes when he's in the middle of class.


Omegas can't be Heroes. Omegas are to be kept at home, safe and sound, not running around the city fighting crime. Omegas are fragile, precious, important for the world. All of these words were drilled into Izuku Midoriya's mind from the time he was a small child and presented as such. It was his greatest dream to become a pro hero like All Might. His dream had come true when he ran into the Pro Hero on that fateful day. Two and a half eventful years had passed, and he had made it into the school of his dreams. Despite being "physically disadvantaged" and "weaker" than his Alpha and Beta classmates. Izuku had immediately bonded with Uraraka and Yaoyorozu, the only other Omegas in the class. The three of them were treated as equals by everyone in class, except for the few weeks in the middle of the year when each girl disappeared, each Alpha in the class on edge for the entirety of it. Except, oddly enough, Todoroki. The only Alpha to be less inclined to aggressive tendencies or agitation. Midoriya secretly thought he was a Beta, had it not been for his scent on occasion. Izuku's Heat hadn't hit him by the age of 17, despite the doctors telling him it could come at any time. Everything for it was under his bed, shoved as far away from him and his thoughts as possible. Izuku hated his own biology and how fate twisted for him. He had to work twice as hard to catch up to Todoroki or Bakugo, but it wasn't all bad. Part of what made him Omega made him a great hero, same as All Might. Izuku was, currently, sitting in class. Midnight was up at the front, going over her lesson for the day when Izuku felt something come over him. He felt sick and loosened his tie, thinking a flu had possibly come over him. Shoto Todoroki turned towards him, looking almost murderous. Katsuki Bakugo was also looking at Midoriya, eyes blown bright wide and his face murderous. Aizawa practically leaped out from behind the desk, shedding his sleeping bag as he did, and bustled Izuku out of his chair. Of course, his Heat had come at the most inopportune moment, creating quite the scene as little less than half the class turned towards him with hunger on their faces. Midnight was up at the front of the class, attempting to collect a semblance of focus back from her students.

Aizawa rushed Midoriya back to the dorms, asking him questions along the way. He answered them robotically, progressively getting hotter and hotter the further they walked. It got to the point of Aizawa carrying Izuku as they walked. Izuku was babbling as they walked, almost out of his mind with a primal _want_ he had never experienced before. They got to the dorms unaccosted, the other teachers having been called in to help. Aizawa opened the door to Izuku's room, turning on the light. The boy instantly shied away from it, closing his eyes and stumbling to his bed. It was piled high with blankets and pillows and he immediately nested within it. Aizawa pulled out the clear container from underneath the bed, putting it at the foot. He closed the window and the curtains. He opened the plastic container, finding the Scent Blocker. He slid it onto the door jamb. It wouldn't be foolproof, but it would definitely help the Alphas in his class.

"I'll return with food and water," Aizawa said, before closing the door behind him. The Beta returned a few minutes later with a tray of essential foods for at least the next three days. There was water in Izuku's mini fridge under his desk. "You'll be excused from class until this ends. UA understands what you're going through." The light was flipped off, the door locked, and Midoriya was left in darkness. When his teacher was gone, Midoriya finally opened his eyes with a soft moan. He felt empty and lonely and hot. Clothes were restrictive, so he tore them all off in a panic, throwing them in the general direction of his laundry basket. There was a huge hole in the pit of his stomach, one that Izuku needed to fill. He turned towards the plastic box, looking at the contents. He was disgusted with himself as he pulled out a slender black toy. There was a petite bulb at the bottom, right above the flared base, that Midoriya could clench around and ride this Heat out. Grabbing it and kneeling on the bed, Midoriya slicked two fingers between his cheeks, feeling how warm and soft it was there. Slipping one in experimentally, he bit down on a moan as he stroked his entrance. It was swollen with need, opening to his ministrations easily. Feeling like a whore, Midoriya braced the toy against his hole and slowly slid it in. He began, almost instantly, to pant, his eyes rolling up in his head as it breached him. He didn't feel complete, and the Omega wasn't nearly satisfied with the cold feeling, but it was better than nothing. It was better than an Alpha pinning him to the bed and riding him out through his Estrus. The thought of a figure pressing into Izuku from behind instantly drove him wild, and he ground against the toy with all of his might, trying to find the climax of his pleasure. For whatever reason, Todoroki's face applied itself to the faceless Alpha of Midoriya's crazed fantasy. In his thoughts, he pressed Midoriya to the mattress, ass up and in perfect position. Todoroki would be bigger than the toy, his knot filling Midoriya to the brim with his seed and consequently his babies. Midoriya wanted nothing more than Todoroki biting into his neck, marking him as his and driving him into the mattress as they made rough love over and over again. With that thought, Izuku came over his sheets, screaming as he did. He looked down at the ruined sheets, sighing softly as the urgent need was satiated for a moment. Groaning with the toy still in him, Izuku stripped his bed and replaced the cover with the waterproof one in the plastic tote. It wasn't long before he was diving into the blanket nest once more and trying to sleep off his Heat.

Consciousness returned to Midoriya slowly, hearing arguing outside of his door. It sounded like some of his classmates, their voices rising with frustration and fierce competition. Midoriya rubbed his legs together, realizing one of those voices was Todoroki's. Again, the need was heightened to an almost unbearable pain and he let out a soft moan and threw off the covers. It released a fresh wave of his scent that undoubtly carried outside to the four alphas standing in the hallway. He heard an almost animalistic growl from one of them and something hit the wall before everything fell silent. Midoriya panted, looking up at his ceiling and thinking about what could possibly be outside. Well, more like _who_ could be waiting outside. If anyone was. Izuku lay in his bed, surrounded by blankets, filled with a toy in the beginning stages of his first heat. He wanted nothing more in the world than to be filled by an Alpha. He froze as there was a quiet knock on the door. He couldn't breathe, he couldn't do anything as there was another knock.

"H-hello?" Izuku's throat felt raw and his body felt too hot, the Heat ramping up from the possibility of a mating partner.

"I know this isn't the best time." There was raw emotion in Todoroki's muffled voice from the other side of the door. "But I've wanted you since the first time I saw you." Midoriya let out a quiet whimper as he rolled over onto his knees, hiding his face in his pillow. "I wanted to know… if you'd let me in. If you don't, or don't feel this is the right time to have this talk or nontalk. I want you, and I'll wait to know if you want me too. Don't worry about any other Alpha coming to break down your door." There was a thump against the door that made Izuku jump. "I'll be here waiting. Don't feel pressured to choose right now. I need to protect you." The thought of Todoroki sitting outside the door while Midoriya pleasured himself brought another wave of slick wetness between his buttcheeks, and a hardness between his legs. Another thought almost immediately replaced that one, of a firm hand on the back of his neck, a warmer better knot replacing the fake one. Izuku stood up on wobbly knees, thinking about it. His crush on Todoroki was something he never expected to actually be reciprocated. The Omega walked to the door, flipping the lock and holding his breath.

"I… uhh… reciprocate those feelings," he almost moaned against the door, resting his forehead against it for a moment before stepping back. The door opened immediately to allow in Todoroki. The young man stepped inside, closing the door behind him and locking it. "Todoroki…"

"Call me Shoto," Shoto replied, voice gravelly. He towered over Midoriya, making the Omega feel small and weak in the best kind of way. Shoto's hand lifted, sliding underneath Midoriya's ear and around the back of his neck. He took a deep breath through his nose, letting out a quiet growl.

"Shoto," Midoriya whispered, stepping towards him and pressing his body against Todoroki's. "I need you." A strangled noise left Shoto's throat, and he began crowding him towards the bed.

"I've waited years to hear you say that." Fingers tightened on the back of Midoriya's neck and he brought him up for their first kiss. Their lips pressed tightly together, rough and needy. Izuku's clumsy fingers began unbuttoning Todoroki's pants, needing skin. His Heat was becoming incomprehensible. The Alpha took over, Todoroki pushing Midoriya to the bed. "On your knees," he commanded, tearing off his clothing and toeing out of his shoes. The Omega obeyed immediately, mewling as he rolled over and presented. A minor amount of his lubrication slid down his perineum and onto his scrotum. Warm fingers wiped it, heading up and to the black silicone base of the toy. "You aren't to use this again, unless I am absolutely indisposed, or I instruct you. Do you understand?"

"Yes Shoto," Izuku keened, bucking his hips once before presenting himself again.

"Good, Izuku," Todoroki replied quietly, more aroused than he had ever been in his entire life. He gripped the base, sliding it out easily. Two fingers replaced the toy, spreading his slickness.

"Please, Shoto," Izuku began babbling, bucking against the fingers and gripping the blankets underneath him. "I need you to stave the need. I need your cock. Right now, 5 seconds ago." Unable to contain himself, Shoto slid in and Izuku keened. "It feels so good, your cock, I want it. I want you." Shoto gripped Izuku's hips, growling and reaching down to grip the dark green sweat slick curls. He covered Izuku with his body, driving him into the mattress as instinct took over. He moved against him over and over, sliding in and out easily. He spanked Izuku's side with his free hand, using his hip as leverage to move against his new love. There was a heat unfurling inside of Izuku from the addition of Shoto's cock. He could feel his climax arriving with every stroke of Todoroki's hips, and Izuku pressed his hand against the wall to give him more leverage to push back against Shoto. Shoto reached forward, activating his quirk to scratch cold fingers down Izuku's back. "Shoto, I'm gonna."

"Come for me, Izuku," Shoto commanded, and Izuku obeyed immediately, writhing on the sheets underneath Todoroki. He slid out, panting and grinning down at Izuku. "Beautiful." Izuku rolled over, gazing up at him. Hands caressed his face gently, soothing away the tears on his cheeks. He brushed back the dark green, almost black, curls from Izuku's face, giving his Omega a gentle kiss. "Do you need anything?"

"Yes, Shoto," Izuku almost whispered, savoring his first name and hooking his legs around Todoroki's hips. "I need to be knotted." Those simple words shot straight from Shoto's ears to his cock, and he let out a groan. "Don't treat me like I'm fragile."

"As you wish." The taller man got up for a moment, looking into the plastic bin for a condom. Hopefully, whoever put this together had enough foresight. Thank god someone had, and he ripped it open. This was a new daunting task that had a very sweaty Midoriya grinning.

"Are you having issues?" Midoriya gently teased as he watched Shoto pull out the instructions from the box and peruse them real quick before rolling it onto himself and joining Midoriya back in bed. He hooked his legs over Todoroki's hips, pulling him closer and hitching his hips higher. Shoto slid his arms around Izuku's back, pulling him up so he was sitting on his lap. Izuku flushed, his entire face turning a bright red. Shoto kissed him roughly, holding the small man up easily. He slid in once more, flicking his tongue against Izuku's lips and drank in Midoriya's moan. "You feel so good." Todoroki pushed up farther, pulling Izuku down against him and gripping Izuku's mildly interested cock in his hand.

"It's so small," Todoroki teased, smiling. "So cute, just like you." They built up an easy rhythm between the two of them, a slow motion gaining speed the more crazed both of them became with the sheer amount of hormones between the two. Waves of Heat Pheromones had been emitted from Izuku as they rocked together, their lips becoming red and swollen with their kisses and shared nips. Todoroki groaned low, possessively, as he pushed Izuku onto his back and took him over and over. Pressing his nose against Izuku's lifeline, he licked a long stripe up the sweat soaked neck. "Should I claim you?" he growled. "Show everyone you're mine for the rest of our life?" Izuku scratched up the muscular back on top of him, moaning and showing his neck in submissiveness.

"Please," he keened. "Mark me. Make me yours." Shoto could feel his knot growing, knew what was coming. He grabbed Midoriya's hair, pulling his face aside so he could bite down on the flesh in front of him. With his orgasm on the very edge, he pressed his weight against Izuku, his knot swelling to fullness. The Alpha bit down, breaking the skin between his teeth and moaning softly. Izuku clenched around his knot, orgasm ripping through both of them as he left angry red scratches down Shoto's back. Gentle hands soothed down the Omega's side, petting him and comforting him. Izuku held onto Shoto, returning kisses from him as he gave them.

They lay there knotted together for what felt like hours, enjoying the post orgasm bliss. Shoto wrapped his arms around Izuku tightly, rolling them around gently so Midoriya can lie on his chest. "Thank you," Izuku whispered into the dark curls. Shoto smiled.

"Thank you for letting me in." Midoriya leaned up to press a soft kiss against Shoto's lips, happy with his social status for the first time in forever. His first heat was sated, for this moment, he was held in his love's arm, and he was marked. The repercussions of that at such a young age was something neither of them wanted to face at this moment in time. The two lovers passed out, blankets strewn across the bed and the two of them pressed together in young love.


End file.
